Competitive autocatalysis in reaction-di†usion systems

The behaviour of a system comprising two competitive autocatalytic processes, A ] B] 2B, and A] C] 2C, rate \ k1a6 b 6 where and represent the concentrations of the various species, is considered. In a well-stirred batch reactor, the rate \ 2 a6 c6 , a6 , b 6 c6 Ðnal equilibrium composition always corresponds to a mixture of the two product species B and C, with their respective equilibrium concentrations depending on the ratio of the rate coefficients and the initial concentrations and If the i \ 21 0 0 . same reactions are carried out in a reaction-di†usion system, with local initiation of the reaction at one end of the reactor, travelling waves of reaction develop. This system can show exclusive product selectivity, with only one of the products being formed in the reactor, provided either the rate coefficient ratio i or the di†usion coefficient ratio di†ers from unity. If d \ BC both di†er from unity the system will select pure production of B if d [ i and pure production of C otherwise. Some interesting complex transient behaviour close to the marginal condition d \ i is reported.